By Nat
The main crux of my PhD is looking to see how personality and performance of an individual affects their vulnerability to predation.
The first component of my PhD is understanding how an individual’s personality affects their chances of being spotted by a predator. Moving throughout and feeding in conspicuous (read: open) foraging locations is risky business for any quoll, as both of these behaviours greatly increases their odds of being spotted. Some quolls may choose to play it safe, and feed in less risk-prone areas or reduce their foraging time in open patches. Other quolls may throw caution to the wind, and stay out in the open, foraging if the food rewards outweigh the costs. This balance between food intake & amount of acceptable risk varies between individuals, creating a spectrum of quoll personalities. Simply put, some quolls are bolder or shyer than others. I have developed a methodology that allows me to score how bold or shy an individual is, all captured on candid camera out in the bush:
Quolls come and search for pieces of bait hidden within the sand, and my infra-red CCTV cameras film their foraging behaviour. I compare the footage against a photo catalogue of all my quolls I have caught during the year, and with a lot of frustration and time, can individually ID the quolls. By knowing who’s who, I can score how bold they are with regards to their foraging decisions.
Quolls foraging through sand for hidden bait
A leopard can’t change its spots; neither does a quoll. Each quoll has a different pattern of spots just like a fingerprint
Each camera is powered by 12volt batteries that weigh 6kg each. Needless to say, setting up & taking down my 20 camera-experiment is back-breaking. To make matters worse, everything needs to be waterproof so these batteries bake in sun in an enclosed box all day, dramatically reducing their charge. My poor volunteers and I were hauling fresh batteries almost every other day through our rocky fieldsite…an OH&S nightmare.
Something smells fishy- making sardine oil to scent the bait; Waterproof battery boxes with a quoll poop garnish; The joys of hauling 6kg batteries once again
Last year, I was extremely lucky enough to receive the Holsworth Wildlife Research Endowment from the Ecological Society of Australia (ESA). This grant allowed me to purchase solar panels for my camera set-up, meaning I didn’t have to replace dying/dead batteries every other day. These solar panels meant I can collect better data (and for longer), dramatically reduce the intensive labour costs of this setup, and as a bonus, decrease my carbon footprint for electricity usage. A trifecta of science gains, all thanks to the ESA and their grants for PhD students. When the Groote sun may cook my brain on a daily basis, at least I’m putting a bit of it’s fury into good use.
New solar panel set-up, propped up by specimen tubes. Need to be resourceful while conducting research on a remote island
To address the second part of my PhD (ability to escape the predator), I need to understand the locomotive capabilities of the quolls. The long-term aspect of the northern quoll study on Groote Eylandt means I have access to experimental designs that the Wilson lab have perfected over the years, helping us quantify an animal’s locomotive performance. These include max sprint speed, acceleration, and agility- how fast can an individual run around a corner without crashing. In other words, our quolls perform Olympic feats for us while being filmed by high-speed cameras, so we can attempt to understand their ability to evade a chasing predator. Some quolls go above and beyond our standardized tests, which is visible in the video below. This video goes to show just how nimble & agile quolls are, this Matrix-like move is about 1m from the ground.
video to be added
The 2018 data collection year started off with a bang, Chopper was my lucky volunteer for the first 6 week trip. I think he now has a complete understanding on how different his Groote experiences are than mine… studying humans can have perks (like a 9-4pm workday). We averaged 13hours days every day and trapped an astounding total of 104 quolls within our 128 hectare field site, a 25% increase in population from last year.
The fun never stops: hauling traps back out into the grids
Chop catching us much needed protein
Quite a few evenings finished in the last rays of sunlight
One perk of battery hauling: it makes that booty round
Crazy weather plagued this trip, Cyclone Marcus shut down trapping for almost a week, and our trip was rudely cut short by Cyclone Nora. We flew off island shortly before the rains & wind ramped up. The trip was overall a smashing success, and a great start to 2018 on Groote. The May trip will have 7 Wilson Lab hooligans descending onto the island, so stay tuned for those shenanigans.
Moody skies before the cyclone
Wonders of nature: a flashy moth and 3 bandicoot joeys whose eyes are just beginning to open